Quick Facts

Francois leaf monkey

Trachypithecus francoisi

Habitat

Francois Langurs are found in small populations in semi-tropical monsoon and moist tropical and sub-tropical rainforests in southern China, and north-eastern Vietnam.

Natural behavior

The arboreal T. francoisi is diurnal, and is extremely agile, adept at jumping from tree to tree. Males have been known to maintain their territories through loud vocalization and displays. There are observations that a dominance hierarchy exists among the females of the species which seem to initiate socialization in the group.

Description

The Francois Langur has a long black tail with distinctive white side burns that start from the ear and finish at the corner of its cheeks.

Distribution

China and Vietnam.

Diet

Although mainly folivorus, the Francois Langur also supplements its diet with flowers, fruit, shoots and bark.

Reproduction

The male François' langurs reach sexual maturity at 5 years, whereas the females reach it at 4 years. The gestation period for these monkeys is 6-7 months.

Social structure

François' langur lives in groups of four to 27 langurs, but will usually be found in groups around 12. they lives in a matriarchal society where the females lead the group. Within the society, the females share parenting responsibilities with one another, and are philopatric to the group. Males within the group take no part in the raising of the young, and the young males leave the group before reaching sexual maturity. Young langurs are nursed up to two years before being weaned, and once weaned, the relationship amongst the relatives becomes that of any other member of a given group.

Threats

In Vietnam, the major threat to this species is hunting, although some populations face pressures from mining and other resource extraction.
The isolation of populations due to habitat fragmentation taking place for agricultural development threatens the genetic viability of small populations.
In some areas of China, the threat of hunting is extremely severe, due to the illegal production of “black ape wine,” which is made specifically from this species; the animals are even imported illegally from Viet nam for this purpose.
In China, populations are threatened by habitat loss due to local cultivation and wood cutting for firewood.
Unmanaged fires that spread into limestone karst habitats also result in the loss of habitat.